Add #656 to CHANGELOG

Author: pluma

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Fixed
+
+- Added `uuid` and `padded` to legal `KeyGeneratorType` values in TypeScript ([#656](https://github.com/arangodb/arangojs/issues/656))
+
 ## [6.14.0] - 2020-03-18
 
 ### Added